Spark-plug



E. ROGERS.

SPARK PLUG. APPLlCATlON FILED JULY 39, I9l9.

1,340, 74. I Patented May 18, 1920 ERNEST aoenas, or CLEVELAND, onro.

srmx-rnue.

' Specification of Letters Patent."

Patented May 18, 1920.

v Application filed July 30. 1919. 7 Serial No. 314.236.

To all whom it may concern:

Be it known that I, ERNEST Rooms, 21-

citizen of the United States, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented certain, new and useful Improvements in Spark-Plugs, of which the following is a. specification,

reference being had to the accompanying drawings.

This invention relates to an improved spark plug, for use in connection with internal combustion engines and one of the objects of the .invention is to provide .an improved device of this kind, which is simple, efficient and practical in construction and maybe manufactured for a relatively low cost and sold ata reasonable into the spark plugcasing,

A further object of the invention is to provide an improved spark plug, comprising a spark plug casing to hold and support thelower porcelain electrode holder, in combination with a holding cap ring threaded porcelain holder a acent the first porcelain holder, whereby a second electrode may be held and supported, so that the second electrode can be easily and conveniently adj usted.

The invention further aims to provide means whereb the second'electrod'e may be adjusted relatively to the first electrode, for

regulating the gap between the two elec- A trodes, in order to increase or decrease the spark between the lower terminal of the first 7 electrode and a terminal which iscarried by the spark'plug casing. The adjustability of the second electrode also acts to regulate the heat of the spark. m

A further object of the invention is to provide a metallic. uide mounted in the vention may be susceptible to changes, and Y upper porcelain hol er, for the upper electrode, in combination with means for supporting the guide in the porcelain holder.

A further feature of the invention is the conductor or While the design; and construction at present set forth and illustrated is deemed preferable, it is obvious that as a .result of a reduction of the invention to a more practical form for commercial. purposes, the inthe right to these changes is claimed, proto hold a second.

, what loose in the bore 8.

' vided they are comprehended within the scope of what is claimed.

The invention comprises further features and combination of parts, as will be hereinafter set forth, shown in the drawings and claimed.

In the drawings:

Figure 1 is a view in side elevation of the improved spark plug constructed in accordance with the invention.

Fig. 2 is a vertical sectional view through the same.

Fig. 3 is a plan view.

Fig. 4 is a detail view of the member to which 'a lead or conductor is connected for conve ing current to the second electrode.

Re erring more especially to the d'rawings, 1 designates as ark plug casing, the reduced portion 2 0 which is exterlorly threaded, so as to thread into an opening of the wall 3 of the combustion chamber, of .an

9 of the porcelain holder extends through the smaller portion .of the casing 1, while the larger portion of the holder engages the larger interior portion of the casing. The upper part of the bore 8 is counter-bored, to provide a recess 9, while the lower portion of the bore 8 is likewise counterbored,

to provide an elongated chamber 10. The

bore 8 receives t e lower electrode 11, which is exteriorly threaded, as shown at '85 provided with a bore 8. The lower portion 12, but which threads 12 do not thread into the bore 8, in fact the electrode 11 is some- A nut 13 is threaded on the electrode'll and is designed to engage the shoulder 14, which is intermediate the bore 8 and the counterbored .portion 10. In fact, this shoulder 14 is at the junction of the bore 8 and 'its counterbored portion 10. While the nut 13 is threaded upon the electrode and is capable of adjustment, nevertheless when the electrode is in position, it is the design of the inventionto fixedly position the nut.

Engagingon the upper end of the electrode 11 is a washer 15, which engages the bottom of the recess 9, and threaded upon the upper end of the electrode 11 and in contact with the washer is a nut 16. B

means of this nut 16, the electrode is held in position in the porcelain holder 7, with the nut 13 in contact with the shoulder 14:. The lower end of the electrode coiiperateswith the terminal of the lower marginal edge of the casing 1, to create a jump spark, 'where-' by the charge in the explosion chamber of the motor may be ignited.

- A cap ring 18 isthreaded into the upper part of the casing 1, and the interior of the cap ring 18 has a shoulder 19. A

second porcelain electrode holder 20 is provided. This porcelain holder 20 has an enlargement 21 at its lower portion, there being a shouldenadjacent the shoulder The porcelain holder 20 rests upon and contacts with the porcelain holder 7,. the-two porcelain holders are held in such positions by screwing the cap ring firmly intothe casing 1, thereby drawing the upper porcelain holder closely in engagement with the lower holder. The body of the upper porcelain holder 20 is tapered and has,

shoulder 26. A. conductor plate 30, which is U-shaped, is provided. This U-shaped conductor plate comprises long and short arms 31 and 32. The longer arm 31 has an opening 33, through which the upper end of the guide sleeve passes, there being a lock nut 34 threaded upon the upper end of the guide sleeve, to cooperate with the nut 29, to hold the conductor plate firmly in position on the guide sleeve. The longer arm 31 also carries a binding screw-35, to

which a wire or lead 36 is connected, for

conveying current from the battery (not shown) to the conductor plate and thence to the upper electrode.

The upper electrode 27 is mountedin the guide sleeve, and its upper portionhas a threaded enlargement38, which is threaded throu h the shorter arm 32 of the conduotor p ate. This threaded enlargement 38 has a thumb piece or finger engaging head 39, whereby the upper electrode may be adjusted, to increase or decrease the gap between the lower end of the upper electrode and the upper end of the lower electrod'e. By increasing or decreasing the gap between the. two electrodes in this manner, the spark between the lower electrode and the terminal of the casing may be increased or decreased, as well as governing the head of the spark. A dowel pin 40 is fixedly though removably mounted transversely of the threaded enlargement 38. This dowel pin is located below the shorter arm 32 of the conductor plate, and constitutes means to limit the upward adjustment of the upper electrode.

Engaging between the shoulders 19 and 23 is an asbestos washer 19". Engaging the shoulder 26 of the counterbored portion 25 of the porcelain holder 20 is an asbestos washer 20. Engaging between the two porcelain holders is an asbestos washer 20", and engaging between the porcelain holder 7 and the-shoulder 5 is an asbestos washer 7.

The invention having been set forth, what is claimed as new and useful is:

1. In a spark plug, the combination with a' spark plug casing for engagement with the wall of the combustion chamber of the motor, of a porcelain electrode holder mounted in said casing, an electrode mounted in said porcelain holder, the lower end of the casing having a sparking terminal to cooperate with the lower end of saidelectrode, a second porcelain electrode holder super-imposed and in contact with the first holder, means on said casing to hold the two porcelain holders in position, guid ng means in the second porcelain holder, a second electrode mounted in the guiding means and having means whereby the second electrode may be adjusted relatively to the first electrode, and a conductor platecarrled by the guide meansand being engaged by thesecond electrode.

2. In a spark plug, the combination with a spark plug casing havin a sparking terminal at one end, of an insulating holder mounted therein and including an electrode, a second insulating holder having uide means, means detachably en aging sai casing for drawing the two hofiiers together, a conductor plate mounted on the guide means, a second electrode adjustably mounted in the conductor plate, whereby its lower end may be adjusted relatively ,to the upper end of the first electrode. a

3. In a spark plug, thecombination with a spark plug casing havin a sparking termay be adjusted relatively to. the upper end of the first electrod e and means carried by the seeondelectrode ior limiting the same in its adjustment.

4. In a spark plug, the combination with a spark plug casing having a sparking ter minal at its lower end, of an. insulating holder mounted therein and including an electrode to cooperate with thesparking terminal, a second insulating ho der, means adjustably carried by the casing to hold the two insulating holders together, and a uide sleeve in the second holder, a U-shape conductor' late carried b the upper end of the guide s eeve, a secon electrode ad'ustably mounted in one of the arms of the U -Shaped conductor plate and guided in-the sleeve,

- whereby its-lower end may be adjusted rela- 'tively to the first electrode.

l 5. In a spark plug, the combination with a-spark plug casing havin a terminal-at one end, of an insulating older mounted therein and including an electrode to cooperate with said s arking terminal, a second insulating hol er, means adjustable on the casing for drawing the two holders together, guide means in the second holder, a U-sha d conductor plate comprisin long and s ort arms removably mounte upon ' x said guide means, the longer arm having a binding post for a conductor wire, a second electrode threaded into the shorter arm of the conductor plate and extending through the guide means, and adapted to be ad usted relatively to the first electrode, and means carried b the second electrode and cooperatin wit the shorter arm, to limit the "secon electrode in its adjustment.

6. In a spark plug, the combination with Y a spark plug 'casi for en agement with the wall of the COEfilllStiOIl c amber of the motor, of an insulating electrode holder mounted in said casin an electrode mounted in said holder, t e lower end of the casing having a s arking terminal to cooperate with the ower end of said electrode, a second insulating electrode holder superimposed and in contact with the first holder, means on said casing to hold the two.

holders in position, guiding means mounted in the second holder, a conductor plate ad- 'justably carried on the u per end of the uiding means, a second e eetrode mounted 1n the guidin means and in the conductor plate and having means whereby it may be adjusted relatively to the first electrode.

7 In a spark plug, the combination with a spark plug casing having a sparking tar? minal at-one end, of. an nsulatin holder mounted therein and including an e ectrode,

a second insulating holder having guiding means, means detachably enga 'ng said casing for drawing the two hol ers together,

a conductor plate adjustably mounted on I ERNEST ROGERS. Witnesses:

FRANK Nm'rmog Mas. E. Rosana. 

